Haywood, Delarivier Manley and Aphra Behn were known as "The fair triumvirate of wit" and are considered the most prominent writers of amatory fiction. Eliza Haywood's prolific fiction develops from titillating romance novels and amatory fiction during the early 1720s to works focused more on "women's rights and position" (Schofield, Haywood 63) in the later 1720s into the 1730s. In the middle novels of her career, women were locked up, tormented and beleaguered by domineering men. In the later novels of the 1740s and 1750s however, marriage was viewed as a positive situation between men and women.
Due to the economy of publishing in the 18th century, her novels often ran to multiple volumes. Authors were paid only once for a book and received no royalties; a second volume meant a second payment.
Haywood's first novel, Love in Excess; Or, The Fatal Enquiry (1719–1720) touches on themes of education and marriage. Often classified as a work of amatory fiction, this novel is notable for its treatment of the fallen woman. D'Elmonte, the novel's male protagonist, reassures one woman that she should not condemn herself: "There are times, madam", he says "in which the wisest have not power over their own actions." The fallen woman is given an unusually positive portrait.
Idalia; or The Unfortunate Mistress (1723) is divided into three parts. In the first, Idalia is presented as a young motherless, spoiled, and wonderful Venetian aristocrat whose varied amorous adventures are to carry her over most of Italy. Already in Venice she is sought by countless suitors, among them the base Florez, whom her father forbids the house. One suitor, who is Florez's friend, Don Ferdinand, resigns his suit, but Idalia's vanity is piqued at the loss of an even a single adorer, and more from perverseness than from love she continues to correspond with him. She meets him, and he eventually effects her ruin. His beloved friend, Henriquez conducts her to Padua, but becomes the victim of her charms; he quarrels with Ferdinand, and they eventually kill each other in a duel.
In the second part, Henriquez' brother, Myrtano, succeeds as Idalia's principal adorer, and she reciprocates his love. She then receives a letter informing her about Myrtano's engagement to another woman, so she leaves for Verona, hoping to enter a convent. On the road her guide takes her to a rural retreat with the intention of killing her, but she escapes to Ancona from where she takes ship for Naples. The sea captain pays her crude court, but just in time to save her from his embraces the ship is captured by corsairs commanded by a young married couple. Though the heroine is in peasant dress, she is treated with distinction by her captors. Her history moves them to tears and they in turn are in the midst of relating to Idalia the involved story of their courtship when the vessel is wrecked in a gale.
In the third part, we find Idalia borne ashore on a plank; succoured by cottagers she continues her journey towards Rome in a man's clothes. On the way robbers beat her and leave her for dead. She is found and taken home by a lady, Antonia, who falls in love with her. Idalia later discovers that Antonia's husband is her dear Myrtano. Their happiness is interrupted by the jealousy of his wife, who first tries to poison everyone and after appeals to the Pope to separate them. Idalia is taken to Rome first in a convent where she leads a miserable life, persecuted by all the young gallants of the city. Then one day she sees Florez, the first cause of her misfortunes. With thoughts of revenge, she sends him a billet, but Myrtano, keeps the appointment instead of Florez. Not recognizing her lover, muffled in a cloak, Idalia stabs him, but upon recognizing him is overcome by remorse, and dies by the same knife.
Fantomina; or Love in a Maze (1724) is a short story about a woman who assumes the roles of a prostitute, a maid, a widow, and a Lady to repeatedly seduce a man named Beauplaisir. Schofield points out that, "Not only does she satisfy her own sexual inclinations, she smugly believes that 'while he thinks to fool me, [he] is himself the only beguiled Person'" (50). This novel asserts that women have some access to power in the social sphere, one of the recurring themes in Haywood's work. It has been argued that it is indebted to the interpolated tale of the "Invisible Mistress" in Paul Scarron's Roman Comique.
The Mercenary Lover; or, The Unfortunate Heiresses (1726) is a novella examining the risks women face in giving way to passion. Miranda, the eldest of two heiress sisters, marries Clitander, the mercenary lover of the title. Unsatisfied with Miranda's half of the estate, Clitander seduces Althea, the younger sister, by plying her with romantic books and notions. She gives way to "ungovernable passion" and becomes pregnant. Clitander fools her into signing over her inheritance, then poisons her, killing both her and the unborn child.
The Distress'd Orphan; or Love in a Madhouse (1726) is a novella that relates the plight of a woman falsely imprisoned in a private madhouse. In Patrick Spedding's A Bibliography of Eliza Haywood, he notes that The Distress'd Orphan; or Love in a Madhouse was more "enduringly popular", "reprinted more often, in larger editions, and remained in print for a longer period, than ... Love in Excess" (21). The story recounts the story of Annilia, who is an orphan and heiress. Her uncle and guardian, Giraldo, plans to gain access to her fortune by having her marry his son, Horatio. When Annilia meets Colonel Marathon at a dance and they fall in love, she rejects her uncle's plan and prepares to move out of his home. In response, Giraldo declares she is insane and has her imprisoned in a private madhouse, thus gaining control of her inheritance. Annilia languishes in the madhouse until Marathon enters it as a supposed patient and rescues her.
The Adventures of Eovaii: A Pre-Adamitical History (1736) was also titled The Unfortunate Princess (1741). It is a satire of Prime Minister Robert Walpole, told through a sort of oriental fairy tale.
The Anti-Pamela; or Feign'd Innocence Detected (1741) is a satirical response to Samuel Richardson's didactic novel Pamela, or, Virtue Rewarded (1740). It makes fun of the idea of bargaining one's maidenhead for a place in society. Contemporary writer Henry Fielding also responded to Pamela with An Apology for the Life of Mrs. Shamela Andrews (1741).
The Fortunate Foundlings (1744) is a picaresque novel in which two children of opposite sex experience the world differently, according to their gender.
The History of Miss Betsy Thoughtless (1751) is a sophisticated, multi-plot novel that has been deemed the first novel of female development in English. Betsy leaves her emotionally and financially abusive husband Munden and experiences independence for a time before she decides to marry again. Written a few years before her marriage conduct books were published, the novel contains advice on marriage in the form of quips from Lady Trusty. Her "patriarchal conduct-book advice to Betsy is often read literally as Haywood's new advice for her female audience. However, Haywood's audience consisted of both men and women, and Lady Trusty's bridal admonitions, the most conservative and patriarchal words of advice in the novel, are contradictory and impossible for any woman to execute completely" (Stuart).
Betsy Thoughtless represents an important change in the 18th century novel. It portrays a mistaken but intelligent and strong-willed woman who gives way to society's pressures toward marriage. According to Backsheider, Betsy Thoughtless is a novel of marriage, rather than the more popular novel of courtship and thus foreshadows the type of domestic novel that would culminate in the 19th century such as Charlotte Brontë's Jane Eyre. Instead of concerning itself with attracting a partner well, Betsy Thoughtless is concerned with marrying well, and its heroine learns that giving way to the role of women in marriage can be fulfilling.
The most detailed and up-to-date bibliography available is Patrick Spedding, A Bibliography of Eliza Haywood. London: Pickering and Chatto, 2004.